Vibration-aware data reassignment

ABSTRACT

An aspect of the present disclosure relates to implementing a temporary reassignment of data based on a vibration condition. An exemplary method includes implementing a data operation for a portion of data and detecting a data error during the data operation. The method further includes obtaining an indication of a vibration condition associated with a device with which the data operation is performed and implementing a temporary reassignment of the portion of data based on the vibration condition.

BACKGROUND

The present disclosure relates generally to data storage systems, andmore particularly, but not by limitation, to data reassignment in datastorage systems.

Data storage systems are used in a variety of different applications.Many different types of data storage systems exist, such as solid-stateand non-solid state systems. Flash memory, random access memory (RAM),and dynamic random access memory (DRAM) are examples of solid-state datastorage systems. Further, a disc drive is an example of a type ofnon-solid state storage system. A disc drive includes at least onerotating disc or storage medium for storage of digital information in aplurality of circular, concentric data tracks. Further, the data tracks(or similarly groups of locations in a solid state device) can bedivided into a plurality of data sectors. The storage medium passesunder a respective bearing slider surface. Each slider carries one ormore transducers, which writes information to and reads information fromthe data surfaces of the disc(s). The slider and transducers are oftentogether referred to as a “head.”

In some instances, one or more sectors of the storage medium can becomedefective. For example, it sometimes happens that sectors of a storagemedium become defective during the manufacturing process of the storagemedium. Further, in some instances sectors can become defective duringnormal operation. Defects can arise in any of the data sectors atvarious times during the lifetime of the storage system (grown defects).For a disc drive, grown defects include, for example, invading foreignparticles which become embedded onto a surface of the storage medium, orexternal shocks to the storage system which can cause the transducer tonick or crash onto a surface of the storage medium. Defective datasectors pose either temporary or permanent data retrieval problems. Toaccommodate media defects such as grown defects, a number of sparesectors can be provided on the storage medium. The spare sectors areused to replace defective sectors on the storage medium.

In many embodiments, a data storage system is subjected to momentaryshock and/or vibration which can cause data errors, for example during adata write and/or read operation. For example, data storage systems,such as disc drives, are recently being used to a greater extent inhand-held consumer electronics, such as digital music players, cellphones and personal data assistants. A disc drive in a hand-held devicecan undergo frequent shock events, such as accidental drops. Inaddition, some hand-held devices themselves are active shock generators.For example, a hand-held phone set on a vibration mode causes momentaryshock events during vibration. Even a ring tone on a hand-held phone canprovide a source of momentary shock if the volume is set high enough.

The discussion above is merely provided for general backgroundinformation and is not intended to be used as an aid in determining thescope of the claimed subject matter.

SUMMARY

An aspect of the present disclosure relates to performing a dataoperation in a data storage system. A temporary data reassignment isperformed for a portion of data based on a vibration condition of thedata storage system.

One exemplary aspect relates to a method of performing a data operation.The method includes implementing a data operation for a portion of dataand detecting a data error during the data operation. The method furtherincludes obtaining an indication of a vibration condition associatedwith a device with which the data operation is performed andimplementing a temporary reassignment of the portion of data based onthe vibration condition.

Another exemplary aspect relates to a data storage system, whichincludes a target storage medium, a temporary data storage location, anda vibration detection component. A controller is configured to implementa data write operation of a portion of data to the target storage mediumand detect a data error during the write operation. The controller isfurther configured to receive a signal from the vibration detectioncomponent indicative of a vibration condition during the write operationand implement a temporary reassignment of data to the temporary datastorage location based on the vibration condition.

Another exemplary aspect relates to a method that includes detecting adata error during a data operation and obtaining a vibration status froma vibration detection component. Further, in response to the detecteddata error, and based on the vibration status, the data operation iseither retried or the data operation is reassigned. In response toretrying the data operation, the steps of detecting a data error andobtaining a vibration status are repeated.

These and various other features and advantages will be apparent from areading of the following Detailed Description. This Summary is notintended to identify key features or essential features of the claimedsubject matter, nor is it intended to be used as an aid in determiningthe scope of the claimed subject matter. The claimed subject matter isnot limited to implementations that solve any or all disadvantages notedin the background.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic diagram of one embodiment of a data storagesystem.

FIG. 2 is an exploded perspective view of one embodiment of a discdrive.

FIG. 3 illustrates a schematic diagram of the disc drive illustrated inFIG. 3.

FIG. 4 is a flow diagram of a method of performing a data writeoperation in a data storage system

FIG. 5 is a schematic diagram of one embodiment of a temporary datastorage component.

FIG. 6 illustrates a method for creating the temporary data storagecomponent of FIG. 5.

FIG. 7 illustrates one embodiment of a method for storing data in atemporary data storage component.

FIG. 8 is a schematic diagram illustrating portions of an exemplarytarget storage medium and a temporary data storage component.

FIG. 9 illustrates one embodiment of a method for performing a temporarydata reassignment including a retry loop.

FIG. 10 illustrates one embodiment of a method for writing data storedin a temporary data storage component to a target storage medium.

DETAILED DESCRIPTION OF ILLUSTRATIVE EMBODIMENTS

FIG. 1 is a schematic diagram illustrating one embodiment of a datastorage system 100. One or more of the elements shown in FIG. 1 can beimplemented as part of data storage system 100 or externally to datastorage system 100. System 100 includes a controller 102 configured tocontrol certain operations of data storage system 100 in a known manner.Controller 102 is communicatively coupled to a host device or system 104and is configured to transmit, receive, access, and/or process datawithin system 100. For example, controller 102 can communicate data withone or more devices, components, applications, and/or subsystems ofsystem 100 such as, but not limited to, a transmitter, receiver, datastorage device, format conversion device, encoder (compressor), decoder(decompressor), buffer, multiplexor, or modulator. In the illustratedembodiment, controller 102 is configured to receive data from hostsystem 104 and provide the data to be stored on target data storagemedium 106. Further, controller 102 is configured to access target datastorage medium 106 to retrieve data stored on medium 106. Controller 102can provide the retrieved data to host system 104 and/or othercomponents of system 100. Controller 102 can also be configured, ifdesired, to perform seek operations to locate desired portions ofstorage medium 106. For example, controller 102 can include a servocontroller configured to seek a read/write head to a desired track ofstorage medium 106.

Target data storage medium 106 can include any type of storage mediumconfigured to store data, including solid-state media and non-solidstate media. For example, storage medium 106 can include a hard disc,floppy and/or removable disc, random access memory (RAM),magnetoresistive random access memory (MRAM), dynamic random accessmemory (DRAM), electrically erasable programmable read-only memory(EEPROM), a flash memory drive, and/or any other type of storage device.In one embodiment, storage medium 106 includes one or more hard discs,such as magnetic and/or optical discs.

During manufacture and/or operation, portions of data storage medium 106can become defective. For example, one or more sectors of data storagemedium 106 can experience grown defects. To accommodate defectivesectors, controller 102 can be configured to perform data reallocationor reassignment. For instance, a number of spare sectors (memorylocations) can be provided on target storage medium 106 and can beutilized to replace the defective sectors encountered during operation.

Further, in the illustrated embodiment system 100 can include atemporary data storage component 110 configured to store data.Controller 102 is communicatively coupled to temporary data storagecomponent 110 and is configured to send data to and receive data fromcomponent 110. In one embodiment, temporary data storage component 110is utilized to store data temporarily within system 100. For example,component 110 can be used as a buffer for storing data to be written totarget data storage medium 106. In one embodiment, controller 102 isconfigured to implement a temporary data reassignment such that data tobe written to target data storage medium 106 is temporarily stored incomponent 110.

Examples of temporary data storage component 110 include bothsolid-state media and non-solid state media. For example, temporary datastorage component 110 can include a hard disc, floppy and/or removabledisc, random access memory (RAM), magnetoresistive random access memory(MRAM), electrically erasable programmable read-only memory (EEPROM), aflash memory drive, and/or any other type of storage device. Asillustrated, data storage component 110 can be separate from targetstorage medium 106. Alternatively, all or part of component 110 can beincluded within target storage medium 106.

In some embodiments, system 100 is employed in an environment in whichdata storage medium 106 can frequently be exposed to momentary shock andvibrations due to the portability and/or functionality of theenvironment in which it is located. For example, data storage medium 106can be provided in a consumer electronic device, such as, but notlimited to, portable electronic devices, digital music players, mobilephones, personal data assistants, etc.

In some instances, a momentary shock or vibration can cause a data errorduring a data write (or read) operation to target storage medium 106. Inthe illustrated embodiment, system 100 can also include a vibrationindication component 108 configured to provide a signal indicative of avibration condition to controller 102. For example, vibration indicationcomponent 108 can include a shock detection circuit configured toprovide a signal indicative of a vibration amplitude. Further, vibrationindication component 108 can also be configured to provide servo errorcode associated with a write and/or read operation. For example, aposition error signal (PES) can be generated which gives an indicationof the radial position of a read/write head with respect to particulartracks on storage medium 106. A position error signal (PES) that isabove a threshold amplitude or has some known characteristic canindicate the presence of a vibration during a data operation.

FIGS. 2 and 3 illustrate one particular embodiment of a data storagesystem 200 having a rotatable data storage medium. As illustrated, datastorage system 200 includes a disc drive. However, one or moreembodiments of the present disclosure are also useful in other types ofdata storage systems.

As shown in FIG. 2, data storage system 200 includes a housing 202having a cover 204 and a base 206. As shown, cover 204 attaches to base206 to form an enclosure 208 enclosed by a perimeter wall 210 of base206. The components of data storage system 200 are assembled to base 206and are enclosed in enclosure 208 of housing 202. As shown, disc drive200 includes a disc or storage medium 212. Although FIG. 2 illustratesstorage medium 212 as a single disc, those skilled in the art shouldunderstand that more than one disc can be used in data storage system200. Storage medium 212 stores information in a plurality of circular,concentric data tracks which are further subdivided into data sectors.Storage medium 212 is mounted on a spindle motor assembly 214 by a discclamp 216 and pin 218. Spindle motor assembly 214 rotates medium 212causing its data surfaces to pass under respective hydrodynamic bearingslider surfaces. Each surface of medium 212 has an associated slider220, which carries transducers that communicate with the surface of themedium. The slider and transducers are often together referred to as aread/write head.

In the example shown in FIG. 2, sliders 220 are supported by suspensionassemblies 222, which are, in turn, attached to track accessing arms 224of an actuator mechanism 226. Actuator mechanism 226 is rotated about ashaft 228 by a voice coil motor 230, which is controlled by servocontrol circuitry within internal circuit 232. Voice coil motor 230rotates actuator mechanism 226 to position sliders 220 relative todesired data tracks, between a disc inner diameter 231 and a disc outerdiameter 233.

FIG. 3 is a simplified block diagram of data storage system 200illustrated in FIG. 2 having housing 202. Data storage system 200includes a controller 236 and processing circuitry 234 used forcontrolling certain operations of data storage system 200 in a knownmanner.

Data storage system 200 can include a preamplifier (preamp) 238 forgenerating a write signal applied to sliders 220 during a writeoperation, and for amplifying a read signal emanating from slider 220during a read operation. A read/write channel 240 receives data fromprocessing circuitry 234 during a write operation, and provides encodedwrite data to preamplifier 238. During a read operation, read/writechannel 240 processes a read signal generated by preamp 238 in order todetect and decode data recorded on medium 212. The decoded data isprovided to processing circuitry 234 and ultimately through interface242 to a host device 244.

As illustrated, storage medium 212 is logically divided into a pluralityof data segments. An example data track 236 and example data segments238-241 are illustrated in FIG. 3. In general, data segments 238-241 areconsidered to be data sectors for storage of user data. However, datasegments 238-241 can also be considered data wedges. Data wedges canspan across more than one data sector as well as include partial datasectors.

Data storage system 200 includes servo controller 236 which generatescontrol signals applied to VCM 230 and spindle motor 214. Processingcircuitry 234 instructs servo controller 236 to move read/write head 220to desired tracks. Servo controller 236 is also responsive to servodata, such as servo burst information recorded on medium 212 in embeddedservo fields or servo wedges included in the data tracks. Both trackseeking and track following operations typically include generation of aposition error signal (PES) by PES module 232 which gives an indicationof the radial position of the read/write head with respect to the trackson the disc. In high performance disc drives, the PES is derived fromeither a prerecorded servo disc with a corresponding servo head (adedicated servo system), or from servo information that is embedded oneach recording surface among user data blocks at predetermined intervals(an embedded servo system). The read/write head provides the servoinformation to the servo control circuitry which generates the PES witha magnitude that is typically equal to zero when the head is positionedover the center of the track (“on track”), and is linearly proportionalto a relative off-track distance between the head and the center of thetrack.

Further, data storage system 200 includes one or more vibrationdetection components which provide an indication of a vibrationcondition of system 200. For example, a shock detection circuit can beprovided that determines whether a disturbance (e.g., shock, vibration,etc.) exceeds a threshold amplitude. In the illustrated embodiment, ashock sensor 231 is provided and is configured to generate a shockoutput signal if a vibration amplitude of an observed disturbanceexceeds a threshold level. The shock output signal can simply representwhether the vibration amplitude exceeds the threshold or can indicatethe level of vibration. Shock sensor 231 communicates the shock outputsignal to controller 236. Controller 236 can be configured to controloperation of the data storage system 200 based on the signal from theshock sensor 231. For example, if the signal from the shock sensor 231indicates a vibration amplitude level that exceeds a threshold level, awrite and/or read operation of system 200 can be block or suspended.Further, controller 236 can be configured to implement a retry of ablocked or suspended data operation.

Further, a vibration detection component can include a componentconfigured to check a servo error code associated with a data operation.For example, a position error signal (PES) module 232 can be configuredto generate a PES during a write operation. The PES gives an indicationof the radial position of a read/write head with respect to particulartracks on storage medium 212. The PES can be utilized to indicatevibration within data storage system 200. For example, controller 236can be configured to detect when the PES deviation exceeds a thresholdvalue and, in response, control a data operation within system 200. Forexample, controller 236 can cause at least a portion of the writeoperation to be blocked based on the PES generated by PES module 232.

Further yet, a vibration detection component can include a componentconfigured to receive an indication of a vibration condition from host244. Host 244 is communicatively coupled to controller 236 via interface242. In some embodiments host device 244 can be configured to implementa component (not shown in FIG. 3) that includes a source of vibration orshock. For instance, in the context of a consumer electronic device hostdevice 244 can be configured to active a component, such as a vibrator,ringer, and/or speaker, that generates a vibration within system 200.Host 244 can provide an indication that a source of vibration is aboutto be activated. Controller 236 can be configured to control dataoperations (e.g., data read and/or write operations) based on vibrationindications received from host device 244.

Sometimes, data segments can become defective or “bad” during normaloperation of data storage system 200. For instance, during operation ofsystem 200 one or more segments (e.g., sectors 238-241) on medium 212can be determined to contain a media defect. For example, segments ofmedium 212 can experience grown defects which include, for example,invading foreign particles which become embedded onto the surface of thedisc, or external shocks to the storage system which can cause thetransducer to nick or crash onto the surface of the disc. Such mediadefects pose either temporary or permanent data retrieval problems.

In accordance with some embodiments, to accommodate defective segmentscontroller 236 and/or processing circuitry 234 can be configured tocarry out a reallocation or reassignment of data. For instance, storagemedium 212 can include a reserve of spare segments for replacing thedefective segments. If a defective segment is discovered, data in thedefective segment is reassigned to a spare segment. The determination ofthe defectiveness of a segment is often determined during a write orread operation. For instance, during a data operation, such as a datawrite operation, controller 236 can encounter a data error. Thecontroller 236 can implement a data retry in an attempt to correct theencountered data error. In another example, system 200 can be configuredto perform a “mini-cert” operation in which a write verify is performedfollowed by a read operation to determine if the sector contains a mediadefect. If the system 200 determines that a media defect exists, thesystem 200 can perform a data reassignment to a spare sector of medium212.

Further, as illustrated in FIG. 3 data storage system 200 can include atemporary data storage component 270. In one embodiment, temporary datastorage component 270 is substantially similar to component 110illustrated in FIG. 1. Examples of temporary data storage component 270include both solid-state media and non-solid state media. For example,temporary data storage component 270 can include a hard disc, floppyand/or removable disc, random access memory (RAM), magnetoresistiverandom access memory (MRAM), electrically erasable programmableread-only memory (EEPROM), a flash memory drive, and/or any other typeof storage device. As illustrated, data storage component 270 can beseparate from storage medium 212. Further, while temporary data storagecomponent 270 is illustrated within housing 202, it is noted that inother embodiments temporary data storage component 270 can be providedoutside housing 202 and/or remote from data storage system 200.Temporary data storage component 270 is configured to provide one ormore temporary data storage locations for storing data. For example,temporary data storage component 270 can operate as a cache or buffermemory for temporarily storing data provided by controller 236.

As discussed above, data storage system 200 illustrated in FIGS. 2 and 3can be used, for example, in hand-held consumer electronic products,such as digital music players, cell phones, personal data assistants andetc. In such an environment, data storage system 200 can frequently beexposed to momentary shock and/or vibration events due to theportability of hand-held devices in which it is located. Thesevibrations and/or shock events can cause data errors during operation ofsystem 200. For example, burst errors are types of error that datastorage system 200 can experience. Further, vibrations and/or shock cancause the read/write head 220 to significantly deviate from a center ofa desired track of medium 212 thus causing a data error in a data writeoperation to the desired track, for instance. In some instances, thevibration and/or shock can cause system 200 to determine incorrectlythat one or more segments of medium 212 contain media defects. Forexample, vibration and/or momentary shock can cause a data storagesystem to identify sectors as containing media defects and implement adata reassignment to spare sectors of the storage medium even though theunderlying media of the original sector is not defective. During a writeoperation, the data storage system 200 may reassign many of the datasegments attempted to be written, and therefore consecutively reassigndata segments that may not need to be reassigned because the underlyingmedia of the data segments are not defective. This type of behavior isknown as consecutive reassignment. Further, in cases where system 200 isexposed to vibration and/or shock for a prolonged period, data storagesystem 200 may attempt to repeatedly rewrite the same data to manydifferent spare sectors. This type of behavior is known as repeatedreassignment.

Repeated reassignment and reassignment of consecutive data segments canhave many detrimental consequences. For example, repeatable reassignmentand consecutive reassignment of data segments can vastly limit an amountof capacity that a data storage system can utilize. A data storagesystem can run out of precious spare data segment space. A repeatedreassignment consumes at least one new spare data segment for eachrepeat. A disc drive that runs out of spare data segments is unable tohandle new grown defects and functions abnormally. In another example,the host operations can time out. Each data segment in error can undergoa series of time-consuming defect tests before it is finally considereddefective and is reassigned. Consecutive or repeated reassignment cansignificantly prolong write operations. In yet another example, areassignment list or table associated with the spare sectors of medium212 can grow rapidly and become full with repeated and consecutivereassignments. Consecutive reassignments generate many reassignmententries and although repeated reassignment generates only a singlereassignment entry, each reassignment entry due to repeated reassignmentoccupies more space than a single entry because all previously usedreplacement segments must be recorded with the reassignment list suchthat previously used replacement segments will not be used asreplacement segments again upon new reassigning. A full reassignmentlist renders a disc drive unable to handle new grown defects. Further,vibration and/or shock present at medium 212 during a data reassignmentto medium 212 can cause a reassignment table failure in which an erroroccurs while writing data to the reassignment table.

In accordance with one embodiment, processing circuitry, such asprocessing circuitry 234 (FIG. 3), handles write errors during writeoperations and limits, or prevents, false media defects, repeatedreassignment of data segments, and/or consecutive reassignment of datasegments. FIG. 4 illustrates a flow diagram of a method 400 ofperforming a data write operation in a data storage system, such as thedata storage system illustrated in FIG. 3. While method 400 is describedin the context of a data write operation, it is noted that the conceptsdescribed herein can be utilized in the context of other data operationsincluding, but not limited to, data read operations, data processingoperations, data transmit and receive operations, and data accessoperations.

At step 402, a data write operation is implemented. A data writeoperation includes writing data to one or more target locations (such assectors) of a target storage medium, such as storage medium 212. Duringthe write operation, a data error is encountered at step 404. Asdiscussed above, a data error during a write operation can be caused by,for example, a media defect and/or misalignment of the read/write headover the storage medium. For instance, vibration and/or momentary shockcan cause the read/write head to deviate from a desired position over atarget track. The sectors of the target storage medium that aredetermined to contain data errors are referred to as error sectors.

At step 406, in response to the detected data error, an indication of avibration condition present during the data write operation is obtained.The indication can include, for example, an output from shock detectioncircuit, such as shock sensor 231 and/or checking servo error codeassociated with the data write operation. For instance, a position errorsignal (PES) associated with the write operation can be checked. Theservo error code or PES can provide evidence that a vibration waspresent during the data write operation.

At step 408, a temporary data reassignment is implemented based on thevibration condition indication obtained at step 406. For example, thetemporary data reassignment can be implemented at step 408 if step 406indicated that a significant vibration was present during the writeoperation to the error sector at step 402. In the illustratedembodiment, the temporary data reassignment includes storing the datafrom the write attempt at step 402 to a temporary data storage locationat step 410. For example, data can be stored to a temporary data storagelocation in a temporary data storage component, such as component 270illustrated in FIG. 3. As discussed above, temporary data storagecomponent 270 can be positioned within the same housing as the targetstorage medium (i.e., medium 212) or can be positioned remote from thetarget storage medium. In either case, the temporary data storagelocation can also be exposed to momentary shock and/or vibration duringa data write (or read) operation to the temporary data storage location.In one embodiment, the temporary data storage location is configuredsuch that a write (or read) operation of data to the temporary datastorage location is less susceptible to data errors caused by vibrationthan a write operation of data to the target storage medium. Forexample, in one embodiment the temporary data storage location caninclude solid-state memory such as, but not limited to, flash memory.

After the data from the error sector is written to the temporary storagelocation at step 410, the method continues to decision block 412 whereinthe method determines if the write operation has completed. Forinstance, the method returns to step 402 and continues to write data toany remaining sectors of the target storage medium. If block 412determines that the write operation has completed, the method 400proceeds to step 414 wherein data stored on the temporary storagecomponent is written back the target storage medium. In one embodiment,data is written from the temporary storage component to the targetstorage medium after the vibration condition has terminated and/or whenthe data storage system is idle. The data can be written back to theoriginal error sectors of the target storage medium or can be written toa spare sector of the target storage medium.

FIG. 5 illustrates one embodiment of a temporary data storage component500. Component 500 is one example of a temporary data storage componentthat can be utilized in system 200. Component 500 includes a temporarydata store 502 comprising one or more storage locations 503. Forinstance, locations 503 can include sectors or segments of a storagemedium, including solid-state and/or non-solid state storage media.Examples of temporary data storage component 500 include a hard disc,floppy and/or removable disc, random access memory (RAM),magnetoresistive random access memory (MRAM), dynamic random accessmemory (DRAM), electrically erasable programmable read-only memory(EEPROM), a flash memory drive, and/or any other type of storage device.

Temporary data storage component 500 also includes a spare table 504 anda temporary data reassignment table 506. Although illustrated asresiding within component 500, one or more of spare table 504 andreassignment table 506 can be external to component 500. Spare table 504includes information relating to the available spare locations 503and/or their physical location within temporary data storage component500. Further, temporary data reassignment table 506 includes entriesthat map temporary data storage locations 503 to error sector of atarget storage medium (i.e. medium 212) for which data is stored incomponent 500. FIG. 6 illustrates a method 600 for establishingtemporary data storage component 500. At step 602, temporary sparelocations 503 are allocated within temporary data storage component 500.At step 604, temporary spare table 504 is created in temporary datastorage component 500. At step 606, the temporary reassignment table 506is created.

FIG. 7 illustrates one embodiment of a method 700 for storing data intemporary data storage component 500. In one embodiment, method 700 isimplemented by controller 236 illustrated in FIG. 3. Further, in oneexample method 700 is utilized for storing data at step 410 illustratedin FIG. 4.

Method 700 begins at step 702 wherein a portion of data is identified tobe written to temporary storage component 500. For example, a portion ofdata from an error sector of a target storage medium, for example medium212, is identified. At step 704, temporary data storage component 500 issearched to determine an availability of one or more storage locations503. In one embodiment, spare table 504 is accessed to determine thephysical locations of the storage locations 503 in component 500. Forexample, step 704 can determine whether a sufficient number of segmentsor sectors in store 502 are available to store the portion of dataidentified at step 702. If a number of store locations 503 necessary tostore the portion of data are determined to be available, the methodstores the data to one or more storage locations 503 at step 706. Then,an entry is created in the temporary reassignment table 506 that mapsthe one or more storage locations 503 to corresponding error sectors ofthe target storage medium. The entries in spare table 504 and/ortemporary reassignment table 506 can be later utilized in retrievingstored data from component 500.

To further illustrate method 700, FIG. 8 is a schematic diagramillustrating a portion of an exemplary target storage medium 802, suchas storage medium 212. Target data storage medium 802 includes one ormore sectors 803 to which data is written during a data operation. FIG.8 also illustrates a plurality of temporary data storage locations(i.e., spares) 804 of a temporary data storage component (i.e. component500).

As illustrated, data is written to sectors 803 in a sequential mannerwherein data is first written to sectors 0 and 1 of medium 802. Duringthe write operation to sectors 806 (i.e., sector 2), a data error isencountered. A temporary data reassignment is implemented wherein thedata from the write attempt to sector 806 is temporarily stored in aportion 810 of temporary data storage locations 804. Upon writing thedata to portion 810, an entry is created in a temporary reassignmenttable (i.e. table 506). The entry includes data that maps portion 810 toerror sector 806. Next, the data write operations continues such thatdata is written to sectors 3 and 4 of medium 802. At sector 808, a dataerror is encountered. A temporary data reassignment is implementedwherein the data from the write attempt to sector 808 is stored in aportion 812 of temporary data storage locations 804. Upon writing thedata to portion 812, an entry is created in the temporary reassignmenttable. The entry includes data that maps portion 812 to error sector808.

FIG. 9 illustrates one embodiment of a method 900 for performing atemporary data reassignment including a retry loop 921. Method 900 willbe described below in the context of data storage system 200,illustrated in FIG. 2. However, the concepts described below can beimplemented in other data storage system types and configurations.

Method 900 begins at block 902 and a write command is performed at step904. The write command can include writing data to one or more targetsectors of a target storage medium (i.e., medium 212). At block 906, ifthe write command is completed, method 900 ends at block 908. If thewrite command is not completed, the method continues to decision block910 wherein a portion of data is written to a sector of the targetstorage medium. Block 910 determines whether a write error wasencountered during the write operation. If a write error was notencountered, the method 900 returns to block 904 wherein the writecommand continues for any remaining sectors.

If decision block 910 determines that a write error was encounteredduring the write operation, the method continues to decision block 912wherein the write error is verified. For example, a write retryoperation can be performed. If the error has cleared, the method returnsto block 904. If the write error has not cleared, the method continuesto block 914 wherein a vibration condition status is obtained from oneor more vibration detection components. The vibration condition statuscan indicate whether a significant vibration was present at the storagesystem during the write operation. For example, step 914 can includereceiving a signal from a shock detection circuit, such as shock sensor231. The shock detection circuit provides a signal indicative of anamplitude of an observed vibration, for example. Further, step 914 caninclude checking a servo error code. As discussed above, a positionerror signal (PES) associated with the write operation can be checked todetermine if the PES exceeded a threshold value during the writeoperation.

At step 916, the method determines whether a vibration was detected atblock 914. If a vibration was not detected, the method continues toblock 918 wherein a conventional sector reassignment is implemented. Forexample, in one embodiment step 918 includes replacing the defectivesector with a spare sector provided on target data storage medium 212.

If a vibration is detected at decision block 916, the method 900determines at decision block 920 whether the vibration condition hasexceeded a pre-determined threshold duration. If a threshold durationhas not been exceeded, retry loop 921 returns to block 912 wherein themethod 900 determines whether the error has cleared. It is noted thatretry loop 921 can also include an optional decision block 923 thatdetermines if an amplitude of the vibration has fallen to a acceptablelevel before performing a write retry/verify at step 912. In oneembodiment, step 923 is substantially similar to steps 914 and 916.

Upon returning to step 912, a data write retry and/or verify can beimplemented to determine if the write command can be successfullycompleted. If the error has not cleared at block 912, loop 921 continuesto blocks 914 and 916 to determine a vibration condition status. Asillustrated, loop 921 generally indicates a delayed reassignment loopthat repeatedly retries the write operation and detects vibration.

If loop 921 exceeds a threshold duration, decision block 920 implementsa delay timeout wherein the method 900 proceeds to step 922. Step 922determines whether a spare data storage location is available on atemporary data storage component, such as component 500 illustrated inFIG. 5. For example, decision block 922 determines whether a sparelocation is available in the temporary data storage component. If atemporary data storage location is not available, the method 900continues to step 918 wherein the error sector is reassigned to a sparesector associated with the target storage medium (i.e., medium 212). Inthis manner, the data from the error sector is stored to a spare sectoron the target storage medium. If a temporary data storage location isavailable at step 922, the method 900 implements a temporary datareassignment that includes storing the data from the error sector to atemporary storage location at step 924. In one embodiment, step 924implements method 700 illustrated in FIG. 7.

After the data is written to a spare sector on target storage medium(step 918) or to a temporary storage location (step 924), the method 900proceeds to step 904 wherein the write command is continued for anyremaining sectors.

FIG. 10 illustrates a method 1000 for writing data stored in thetemporary data storage component 500 back to the target storage medium(i.e. medium 212). The method begins at block 1001. At step 1002, themethod 1000 determines whether the data storage system is stable and/oridle. For example, step 1002 determines whether the data storage systemis currently performing a data write or read operation, and/or whether avibration is present at the storage system. If the system is notsufficiently idle and/or stable, the method ends at block 1003. If thesystem is determined to be stable, the method 1000 proceeds to decisionblock 1004 wherein the temporary reassignment table is checked todetermine if the table contains at least one entry mapping data storedin the temporary storage component. If the temporary reassignment tableis empty, the method 1000 proceeds to block 1003 wherein the methodterminates.

If the reassignment table is not empty, the method 1000 proceeds to step1006 wherein one or more of the temporary reassignment entries in thereassignment table are retrieved. As discussed above, entries in thereassignment table can contain information mapping data stored in thetemporary storage locations to original error sectors on the targetstorage medium. At block 1008, the original error sectors on the targetstorage medium are checked to determine whether the error sectorscontain a media defect. For example, step 1008 can include a writeand/or read verify.

At decision block 1010, if the original error sector is determined tocontain a media defect the method proceeds to block 1012 wherein theerror sector is reassigned to a spare sector on the target storagemedium. If the error sector passes the test at step 1010, data iswritten from the temporary storage component to the original sector onthe disk. Following a successful write of data at steps 1012 or 1014,the temporary reassignment entry is deleted from the temporaryreassignment table at step 1016 and the method returns to block 1002.

It is to be understood that even though numerous characteristics andadvantages of various examples have been set forth in the foregoingdescription, together with details of the structure and function ofvarious embodiments, this disclosure is illustrative only, and changesmay be made in detail, especially in matter of structure and arrangementof parts within the principles of the disclosure to the full extentindicated by the broad general meaning of the terms in which theappended claims are expressed. For example, the particular elements mayvary depending on the particular application for data sectorreassignment while maintaining substantially the same functionalitywithout departing from the scope of the disclosure and/or the appendedclaims. In addition, although examples described herein are directed toa data storage system for non-volatile storage of data, it will beappreciated by those skilled in the art that the teaching of thedisclosure can be applied to the correction of errors in volatile memoryor dynamic memory, without departing from the scope of the disclosureand/or claims.

1. A method of performing a data operation, the method comprising:detecting a data write error associated with a data write operation fora portion of data to one or more target storage locations of a first,target storage medium; and implementing a delayed data reassignment modefor the portion of data comprising: verifying the data write error aftera time delay and obtaining an indication of a vibration conditionassociated with the data write error; and implementing a temporary datareassignment by storing the portion of data to one or more storagelocations of a second storage medium based on verification of the datawrite error and based on a determination that the vibration conditionexceeds a threshold duration.
 2. The method of claim 1, wherein storingthe portion of data to one or more storage locations of the secondstorage medium includes writing the portion of data to a solid-statememory device.
 3. The method of claim 1, wherein the second storagemedium is separate from the target storage medium, and wherein obtainingan indication of the vibration condition comprises receiving a signalfrom a vibration detection component.
 4. The method of claim 3, whereinobtaining the indication of the vibration condition includes obtaining astatus of a shock sensor and a servo error code associated with the datawrite operation to the target storage medium.
 5. The method of claim 1,wherein the delayed data reassignment mode includes a reassignmentprocess loop comprising: a) imposing a time delay; b) determining if thedata write error cleared after the time delay by implementing asubsequent data write operation to the one or more target storagelocations; c) receiving a vibration status from a vibration detectioncomponent indicative of a vibration condition during the subsequent datawrite operation; d) repeating steps a) to c) until a loop exit conditionis satisfied.
 6. The method of claim 5, wherein the loop exit conditioncomprises at least one of a total time delay exceeding a threshold,receiving a vibration status that indicates a vibration did not occurduring the subsequent data write operation, and determining that thedata write error cleared after the time delay.
 7. The method of claim 1,wherein implementing the temporary data reassignment comprises: creatingan entry in a reassignment table associated with the second storagemedium, wherein the entry maps the one or more target storage locationsto the one or more storage locations of the second storage medium. 8.The method of claim 1, wherein implementing the temporary datareassignment comprises: determining that the vibration condition hasterminated; and in response to the determination, performing anoperation to determine whether the one or more target storage locationsare considered to contain one or more media defects.
 9. The method ofclaim 8, comprising attempting to rewrite the portion of data to the oneor more target storage locations.
 10. The method of claim 9, and furthercomprising: detecting a data error during the re-write; and writing theportion of data to one or more spare storage locations associated withthe target storage medium based on whether a data error was detectedduring the re-write.
 11. The method of claim 1, wherein implementing thetemporary data reassignment comprises reassigning the one or more targetstorage locations to the one or more data storage locations of thesecond storage medium for a period of time that is defined at least inpart by a determination that the vibration condition has terminated. 12.A method comprising: detecting a data error associated with a data writeoperation of a portion of data to one or more sectors of a first, targetstorage medium; obtaining a vibration status from a vibration detectioncomponent, the vibration status being indicative of a vibration thatoccurred during the data write operation; in response to the detecteddata error, and based on the vibration status, retrying the data writeoperation; in response to retrying the data write operation, repeatingthe steps of detecting a data error associated with the data writeoperation and obtaining a vibration status; and implementing a temporarydata reassignment comprising storing the portion of data to one or morestorage locations of a second storage medium if the steps of obtainingthe vibration status indicate a vibration duration that exceeds athreshold duration.
 13. The method of claim 12, wherein obtaining avibration status comprises obtaining a status of a shock sensor andservo error code associated with the data write operation.
 14. Themethod of claim 12, wherein implementing the temporary data reassignmentcomprises: determining whether a storage location in a temporary datastorage component is available, wherein the temporary data storagecomponent includes a solid-state memory device; writing the portion ofdata to the temporary data storage component if a storage location isavailable; and creating an entry in a reassignment table associated withthe temporary data storage component, wherein the entry includesinformation that maps the target sector to one or more storage locationsin the temporary data storage component.
 15. A data storage systemcomprising: a first, target storage medium; a second storage medium thatis separate from the target storage medium; a vibration detectioncomponent; and a controller configured to: implement a first data writeoperation of a portion of data to one or more target storage locationsof the target storage medium and detect a data error associated with thefirst data write operation; based on the detected data error and anindication of a vibration condition that occurred during the data writeoperation, implement a data reassignment operation that stores theportion of data to one or more data storage locations of the secondstorage medium; and after the vibration condition has terminated,perform an operation to determine whether the one or more target storagelocations are considered to contain one or more media defects, accessthe one or more data storage locations of the second storage medium andperform a second data write operation of the portion of data to the oneor more target storage locations of the target storage medium, andreassign the one or more target storage locations to one or more sparestorage locations if the one or more target storage locations areconsidered to contain one or more media defects.
 16. The system of claim15, wherein the controller is configured to perform one or moreiterations of implementing a retry of the first data write operation tothe one or more target storage locations after a time delay andobtaining an indication of a vibration condition associated with theretry, wherein the controller is configured to implement the datareassignment operation if a threshold delay timeout period is reached.17. The system of claim 15, wherein the controller is configured toallocate the one or more data storage locations of the second storagemedium for data storage during a subsequent data reassignment operationfor a portion of data associated with a subsequent data write operationto the target storage medium.
 18. The system of claim 15, wherein thecontroller is configured to implement the data reassignment operation totemporarily reassign the one or more target storage locations to the oneor more data storage locations of the second storage medium for a periodof time that is defined at least in part by a determination that thevibration condition has terminated.
 19. The system of claim 15, whereinthe first storage medium comprises non-solid-state memory and the secondstorage medium comprises solid-state memory.